JPH07259886A - Shaft coupling structure - Google Patents

Abstract

PURPOSE:To provide a shaft coupling structure having high coupling strength in a meshing part and lightening weight, in the shaft coupling structure meshing an irregularity part, formed along the peripheral direction in one end face of one rotary element of forming one end side in a tubular shape, with an irregularity part engaged with this former irregularity part and further formed along the peripheral direction of the other rotary element. CONSTITUTION:In a shaft coupling structure in which irregularity parts 37, 38 formed along the peripheral direction in one end part of one rotary element 32 of forming one end side in a tubular shape, are meshed with irregularity parts 41, 42 engaged with these irregularity parts 37, 38 and further formed along the peripheral direction of the other rotary element 33, so as to transmit torque between these rotary elements 32, 33, diametric directional thickness dimension of an outer edge part 39 in the irregularity parts 37, 38 along the diametric direction of at least the one rotary element 32 is set thick.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concavo-convex portion formed along the circumferential direction on one end face of one rotary element having one end having a tubular shape, and to the concavo-convex portion of the other rotary element. The present invention relates to a shaft coupling structure that meshes with a concavo-convex portion formed along the circumferential direction.

[0002]

2. Description of the Related Art As one of frictional engagement elements of an automatic transmission for a vehicle, a band brake is wound around the outer periphery of a cup-shaped reverse clutch drum, and the transmission output is changed by tightening or releasing the band brake. The one that switches the rotation direction of the shaft between the forward side and the reverse side,
For example, it is known from JP-A-59-29428.

The tip portion of the reverse clutch drum of the automatic transmission disclosed in Japanese Patent Laid-Open No. 59-29428 and the like is
It engages with the tip of the cup-shaped connecting shell connected to the transmission output shaft side, and these engaging portions are formed with crown gear-shaped uneven portions formed along the circumferential direction, It is in a meshed state.

Therefore, when the band brake is opened, the reverse clutch drum rotates integrally with the connecting shell due to the meshing of these concave and convex portions, but when the band brake is tightened, the reverse clutch drum shifts together with the connecting shell. Since it is integrated in the machine case, the inertia torque on the output shaft side of the transmission is applied to the reverse clutch drum side from the connecting shells via the meshing portions between the connecting shells and the reverse clutch drum. In other words, when tightening the band brake, the inertia torque on the transmission output shaft side is directly input to the meshing portion between the connecting shell and the reverse clutch drum, so the coupling strength of these meshing portions is the maximum expected inertial torque. Therefore, it is necessary to raise it sufficiently.

Generally, the reverse clutch drum and the connecting shell are formed by pressing a mild steel plate which is excellent in workability in order to reduce the size and weight of the transmission itself. Since it is necessary to increase the height, the plate thickness of the mild steel plate is increased, or a material having a mechanical strength superior to that of the mild steel plate is used to maintain the bond strength of the meshing portion.

[0006]

SUMMARY OF THE INVENTION Like the meshing portion between the reverse clutch drum and the connecting shell of the automatic transmission described above, it is formed along the circumferential direction on the one end surface of one rotating element whose one end side is cylindrical. The formed uneven portion is meshed with the uneven portion that is engaged with this uneven portion and is formed along the circumferential direction of the other rotating element, and the rotational force is transmitted between these two rotating elements. In the shaft coupling structure, it is general that these rotary elements are manufactured by press working, and a steel plate having a relatively low strength, which is excellent in draw formability, is used as a material thereof.

In order to satisfy the strength of the shaft joint portion made of such a material having relatively low strength, the engagement area of the concave and convex portions that mesh with each other is ensured, and torque transmission is performed at a surface pressure below the allowable stress. It needs to be taken into consideration. That is,
A thick plate material with sufficient thickness must be used. Also, due to the centrifugal force generated when the rotating element rotates at high speed,
Since stress concentration occurs in the corners of the concave portion of the uneven portion, in order to withstand this, it is also necessary to consider reducing the stress level in the stress concentrated portion. In order to increase the strength of this stress concentration portion, one measure is to increase the plate thickness of the material.

However, when the plate thickness of the rotating element is increased, the drawability is deteriorated and the centrifugal force is increased with the increase in weight, resulting in a further increase in the stress applied to the stress concentrated portion. The effect of increasing the plate thickness is not so effective.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a concavo-convex portion formed on one end surface of one rotating element having one end side of a tubular shape along the circumferential direction, and to engage the concavo-convex portion with the other rotating element. An object of the present invention is to provide a lightweight shaft joint structure having a high coupling strength at a meshed portion in a shaft joint structure in which uneven portions formed along the circumferential direction are meshed with each other.

[0010]

According to the shaft coupling structure of the present invention, a concavo-convex portion is formed along the circumferential direction on one end face of one rotating element having one end side of a tubular shape, and the concavo-convex portion is engaged with the concavo-convex portion. And, in the shaft coupling structure in which the concavo-convex portion formed along the circumferential direction of the other rotary element is meshed with each other to transmit the rotational force between these two rotary elements, the diameter of at least one of the rotary elements The feature is that the thickness dimension of the uneven portion along the direction is set thick.

In this case, it is effective that the peripheral edge of the uneven portion is bent outward in the radial direction or inward in the radial direction.

[0012]

According to the present invention, the rotational force is transmitted between the two rotary elements by the engagement between the concave and convex portions of the one rotary element and the concave and convex portions of the other rotary element. Here, since the thickness dimension along the radial direction of the concavo-convex portion of at least one of the rotating elements is set thick, the rigidity of the concavo-convex portion is kept high.

When the peripheral edge of the concavo-convex portion is bent radially outward or radially inward, the rigidity of the concavo-convex portion is improved while suppressing the weight increase of one rotating element.

[0014]

EXAMPLE A shaft coupling structure according to the present invention is used in which four forward stages and one backward stage are used.
An embodiment applied to a connecting portion between a reverse clutch drum and a connecting shell of an automatic transmission of a gear will be described in detail with reference to FIGS.

FIG. 1 showing a power transmission mechanism in this embodiment.
As shown in, the impeller 12 of the torque converter 11 is integrally connected to the crankshaft of the engine (not shown). The torque converter 11 includes the impeller 12, the turbine 13, a stator 14, and a one-way clutch 15. The stator 14 is connected to the transmission case 16 via the one-way clutch 15, and the one-way clutch 15 is provided.
Due to this, the stator 14 rotates in the same direction as the crankshaft, but rotation in the opposite direction is not permitted. Then, the torque transmitted to the turbine 13 is transmitted to the input shaft 17 of the gear transmission that is arranged at the rear portion of the torque converter 11 and that achieves four forward gears and one reverse gear.

This gear transmission has three sets of clutches 1.
It is provided with 8, 19 and 20, two sets of brakes 21 and 22, one set of one-way clutch 23 and one set of planetary gear mechanism 24. The planetary gear mechanism 24 includes an internal gear 26 connected to the output gear 25, a front planetary gear 27 that meshes with the internal gear 26, and the front planetary gear 2
7, a rear planetary gear 28 that is coaxial with the rear planetary gear 28, a rear sun gear 29 that meshes with the rear planetary gear 28 and is connected to the input shaft 17 through the low speed clutch 19, and a rear planetary gear 28 that meshes with the front planetary gear 27 and through the reverse clutch 18 to the input shaft 17. The connected front sun gear 30 and the planetary gears 27, 29 are rotatably supported, and the rear end thereof is connected to the input shaft 17 via the high speed clutch 20.
It is composed of a tubular carrier 31 connected to the rear end. Further, the carrier 31 is connected to the transmission case 16 via a low speed / reverse brake 22 and a one-way clutch 23 which are arranged in parallel with each other.

Front sun gear 30 and reverse clutch 18
A reverse clutch drum 32 having a cylindrical shape and a connecting shell 33 having a disk shape are interposed between the rear clutch drum 32 and the rear clutch drum 32, and the reverse clutch drum 32 can be integrally connected to the transmission case 16 by the band brake 21. ing. The torque that has passed through the planetary gear mechanism 24 is output to the output gear 25.
Is transmitted to the drive shaft side of the drive wheels via a differential device (not shown).

Each of the clutches 18 to 18 which are friction engagement elements
The 20 and the brakes 21 and 22 are each composed of a hydraulic device equipped with an engagement piston device or a servo device, and are not shown in the drawing due to pressure oil generated by an oil pump 34 connected to the impeller 12 of the torque converter 11. It is operated via a hydraulic control device.

The detailed structure and operation are already known, for example, in Japanese Utility Model Laid-Open No. 59-29428, and the position selected by the driver of the select lever provided in the driver's seat (not shown). And the frictional engagement elements are selectively engaged in accordance with the operating state of the vehicle, and various gears are operated via the hydraulic control device based on commands from an electronic control unit that controls the operating state of the engine. Is automatically achieved.

As shown in FIG. 2 which shows the sectional structure of the reverse clutch drum 32 and the connecting shell 33, the cylinder portion 35 of the pump cover integrally bolted to the transmission case 16 is retracted. A boss portion 36 of the clutch drum 32 is slidably fitted, and an inner peripheral portion of a connection shell 33 is integrally joined to a front sun gear 30 that surrounds the input shaft 17 penetrating the tubular portion 35 of the pump cover. Has been done. Then, in the reverse clutch drum 32 and the connecting shell 33, the above-mentioned two clutches 18, 1
9 is incorporated.

As shown in FIG. 2 and FIG. 3 in which the reverse clutch drum 32 and the connecting shell 33 are extracted and disassembled in a broken state, concave portions are formed at predetermined intervals along the circumferential direction on the front end surface of the reverse clutch drum 32. 37 and convex portions 38 are formed alternately, and the outer edge portions 39 of these concave and convex portions 37, 38 are
It is in a state of being bent outward in the radial direction. The bending structure of the outer edge portion 39 remarkably improves the rigidity of the concave and convex portions 37 and 38, so that the bottom wall 4 of the concave portion 37 against the centrifugal force generated as the reverse clutch drum 32 rotates.
It can withstand the stress concentration at the corner of 0.

A concave portion 4 corresponding to the concave and convex portions 37 and 38 of the reverse clutch drum 32 is provided on the peripheral portion of the connecting shell 33.
1 and convex portions 42 are alternately formed in a radial pattern, and the concave and convex portions 41 and 42 of the connection shell 33 and the concave and convex portions 37 and 38 of the reverse clutch drum 32 are in mesh with each other. That is, the side walls 43 of the concave and convex portions 37 and 38 of the reverse clutch drum 32 and the concave and convex portions 4 of the connection shell 33.
By contacting the side walls 44 of the first and the second parts 42, the rotational force between the reverse clutch drum 32 and the connecting shell 33 is transmitted. In this case, the connection shell 33
Are formed in a cylindrical shape like the reverse clutch drum 32, and uneven portions similar to those of the reverse clutch drum 32 are alternately formed at predetermined intervals along the circumferential direction on the tip surface of the reverse clutch drum 32. , 38 and the concavo-convex portion of the connection shell 33 may be engaged with each other in a facing state. It is also possible to bend the outer edge portions of the concave and convex portions 41, 42 of the connection shell 33 in the same manner as the reverse clutch drum 32 and engage with each other.

In this embodiment, since the reverse clutch drum 32 and the connecting shell 33 are manufactured by pressing a sheet metal, the outer edge portions of the uneven portions 37 and 38 can be formed without increasing the sheet thickness of the sheet metal. By simply bending 39, the strength of the uneven portions 37, 38 can be improved,
It is possible to minimize the weight increase due to the improvement in rigidity.

In the above-described embodiment, the entire outer edge portion 39 of the concave-convex portions 37, 38 of the reverse clutch drum 32 is bent outward in the radial direction, but at least the bottom wall 40 and the side wall 43 are outwardly in the radial direction. The same effect as in the above-described embodiment can be obtained only by bending the inside.

As shown in FIG. 4, which shows the fracture structure of another embodiment of the reverse clutch drum 32, concave portions 45 and convex portions are formed on the front end surface of the reverse clutch drum 32 at predetermined intervals along the circumferential direction. The portions 46 are alternately formed, and the side wall 47 and the bottom wall 48 of these concave and convex portions 45 and 46 are bent outward in the radial direction. Due to the bent structure of the side wall 47 and the bottom wall 48,
Since the rigidity of the uneven portions 45 and 46 is remarkably improved as in the previous embodiment, the stress at the corners of the bottom wall 48 of the uneven portions 45 and 46 against the centrifugal force generated as the reverse clutch drum 32 rotates. Can withstand concentration enough.

[0026]

According to the shaft joint structure of the present invention, the thickness of the uneven portion formed on at least one of the pair of rotating elements meshing with each other in the radial direction is set to be thick, so that the rigidity of the uneven portion is increased. Can be improved.

When the thickness of the uneven portion is set to be thick by bending the peripheral edge of the uneven portion radially outward or radially inward, the weight increase of one rotating element is minimized. It is possible to improve the rigidity of the uneven portion in the state of being suppressed to the limit.

[Brief description of drawings]

FIG. 1 is a skeleton diagram showing a power transmission mechanism of an embodiment in which a shaft coupling structure according to the present invention is applied to a connecting portion between a reverse clutch drum and a connecting shell of an automatic transmission having four forward gears and one reverse gear.

2 is a cutaway sectional view of a connecting portion between a reverse clutch drum and a connecting shell in the automatic transmission shown in FIG.

FIG. 3 is a cutaway perspective view of a state in which a reverse clutch drum and a connection shell are extracted and disassembled.

FIG. 4 is a cutaway perspective view showing the structure of another embodiment of the reverse clutch drum.

[Explanation of symbols]

 11 torque converter 12 impeller 13 turbine 14 stator 15 one-way clutch 16 transmission case 17 input shaft 18 reverse clutch 19 low-speed clutch 20 high-speed clutch 21 band brake 22 low-speed / reverse brake 23 one-way clutch 24 planetary gear mechanism 25 output gear 26 in Tooth gear 27 Front planetary gear 28 Rear planetary gear 29 Rear sun gear 30 Front sun gear 31 Carrier 32 Retracting clutch drum 33 Connection shell 34 Oil pump 35 Pump cover cylinder 36 Boss 37 Recess 38 Convex 39 Outer edge 40 Bottom wall 41 Recess 42 Convex 43, 44 Side wall 45 Recessed portion 46 Convex portion 47 Side wall 48 Bottom wall

Claims (2)

[Claims] 1. A concavo-convex portion formed along the circumferential direction on one end surface of one rotating element whose one end side has a tubular shape, and formed along the circumferential direction of the other rotating element by engaging the concavo-convex portion. In a shaft coupling structure in which a rotating portion is meshed with the formed uneven portion and a rotational force is transmitted between these two rotating elements, the thickness of the uneven portion along the radial direction of at least one of the rotating elements is set thick. A shaft joint structure characterized by the above. 2. The shaft joint structure according to claim 1, wherein a peripheral edge of the uneven portion is bent radially outward or radially inward.